540 Capt. Sabine's Memoir on the Birds of Greenland, <^c. 



Nos. 110, 111 and 112, which he calls Svarbag, Ringvia and 

 Alo-a: the two former Iceland and the latter Danish birds: he is 

 undetermined whether these be distinct species, or the present 

 in different states of plumage: I am inclined to consider the 

 latter supposition as the correct one. 



It will be necessary to make some alteration in the specific cha- 

 racter of Uria Troile, as given in Gmelin and Latham, to distin- 

 guish it from Uria Briinnichii. It is therefore proposed to de- 

 scribe the two species as follows : 



U. Troile. U. corpore fusco, pectore abdomineque niveo, remi- 

 gibus secundariis apice albis, rostro longitudine capitis : 

 mandibula superiore quadruplo longiore quam lata. 



V. Briinnichii. U. corpore fuliginoso, pectore abdomineque ni- 

 veo, remigibus secundariis apice albis, rostro capite breviore: 

 mandibula superiore triplo longiore quani lata. 



15. Uria Gryllk. Black Guillemot. 



U. Gr}'lle. Temm. 608. Fabr. 92.— Black Guillemot. Br. Zool. u. 163. 3Iont. Diet. 4f 

 Supp. Lath. Syn. vi. 332. &s Siipp. 265. 



Mature Wintee. U. Grylloides. Brim. no. 114. — U. Balthica. Brun. 

 nos. 115 cV 116. 



Mature Summer. U. Grylle. Br'un. no. 1 13. Ijath. Lid. Om. ii.797. — Co- 

 Ivmbus Grylle. Gmel. 584. Faun. Siiec. 52. — Colynibus Gryllus. Miill. no. 151. — 

 Black Guillemot. Arct. Zool. ii. 5l6. 



The states of plumage of this bird are clearly described from 

 the'extensive and accurate observation of Fabricius. The young, 

 when just feathered, are spotted black and white beneath, but 

 otherwise resemble the parents. On the approach of winter the 

 whole become varied with black and white; the feathers of the 

 back margined with white; the head, throat and breast, white 

 lightly spotted with black, the wings continuing black, and the 



speculum 



